package com.example.graduatetest.utils;

import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Random;

public class TimeGet {
    //获取当前时间
    public static String getDate() {
        Date dNow = new Date();
        SimpleDateFormat ft =
                new SimpleDateFormat("yyyy.MM.dd HH:mm:ss");
        return ft.format(dNow);

    }
    //获取唯一id
    public static String getUId() {
        long time = System.currentTimeMillis();
        String s = String.valueOf(time);
        s=s.substring(3,13);
        long id = Long.valueOf(s);
        System.out.println(s.length());
        return String.valueOf(id);
    }
    //获取随机字符串
    public static String getRandomString(int length) {
        Random random = new Random();
        StringBuffer sb = new StringBuffer();
        for (int i = 0; i < length; i++) {
            int number = random.nextInt(3);
            long result = 0;
            switch (number) {
                case 0:
                    result = Math.round(Math.random() * 25 + 65);
                    sb.append(String.valueOf((char) result));
                    break;
                case 1:
                    result = Math.round(Math.random() * 25 + 97);
                    sb.append(String.valueOf((char) result));
                    break;
                case 2:
                    sb.append(String.valueOf(new Random().nextInt(10)));
                    break;
            }
        }
        return sb.toString().toUpperCase();
    }


}
